/* Copyright (c) 2018, Curtis McEnroe <programble@gmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <linux/fb.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sysexits.h>
#include <unistd.h>

static const char *CLASS = "/sys/class/power_supply";

static const uint32_t RIGHT  = 5 * 8 + 1; // fbclock width.
static const uint32_t WIDTH  = 8;
static const uint32_t HEIGHT = 16;

static const uint32_t BG     = 0x1D2021;
static const uint32_t BORDER = 0xA99A84;
static const uint32_t GRAY   = 0x938374;
static const uint32_t YELLOW = 0xD89A22;
static const uint32_t RED    = 0xCC241D;

int main() {
    int error;

    DIR *dir = opendir(CLASS);
    if (!dir) err(EX_OSFILE, "%s", CLASS);

    FILE *chargeFull = NULL;
    FILE *chargeNow = NULL;

    const struct dirent *entry;
    while (NULL != (errno = 0, entry = readdir(dir))) {
        if (entry->d_name[0] == '.') continue;

        error = chdir(CLASS);
        if (error) err(EX_OSFILE, "%s", CLASS);

        error = chdir(entry->d_name);
        if (error) err(EX_OSFILE, "%s/%s", CLASS, entry->d_name);

        chargeFull = fopen("charge_full", "r");
        chargeNow = fopen("charge_now", "r");
        if (chargeFull && chargeNow) break;
    }
    if (!chargeFull || !chargeNow) {
        if (errno) err(EX_OSFILE, "%s", CLASS);
        errx(EX_CONFIG, "%s: empty", CLASS);
    }
    closedir(dir);

    const char *path = getenv("FRAMEBUFFER");
    if (!path) path = "/dev/fb0";

    int fb = open(path, O_RDWR);
    if (fb < 0) err(EX_OSFILE, "%s", path);

    struct fb_var_screeninfo info;
    error = ioctl(fb, FBIOGET_VSCREENINFO, &info);
    if (error) err(EX_IOERR, "%s", path);

    size_t size = 4 * info.xres * info.yres;
    uint32_t *buf = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fb, 0);
    if (buf == MAP_FAILED) err(EX_IOERR, "%s", path);

    for (;;) {
        int match;

        rewind(chargeFull);
        fflush(chargeFull);
        uint32_t full;
        match = fscanf(chargeFull, "%u", &full);
        if (match == EOF) err(EX_IOERR, "charge_full");
    June McEnroe</td><td><span title='2018-09-02 13:45:00 -0400'>2018-09-02</span></td></tr>
<tr><td class='commitgraph'>* </td><td><a href='/catgirl/commit/pls.c?h=1.7&amp;id=e5663d45df15395cc4650937ed2bde8e29257d27'>Add aswprintf</a></td><td>June McEnroe</td><td><span title='2018-09-02 01:03:12 -0400'>2018-09-02</span></td></tr>
<tr><td class='commitgraph'>* </td><td><a href='/catgirl/commit/pls.c?h=1.7&amp;id=4e4eb0de0f50517e3a2892cddcadfbd75da7152f'>Add wcsnchr, wcsnrchr, awcsntombs</a></td><td>June McEnroe</td><td><span title='2018-08-20 18:43:16 -0400'>2018-08-20</span></td></tr>
<tr><td class='commitgraph'>* </td><td><a href='/catgirl/commit/pls.c?h=1.7&amp;id=afae851319c543118f08b49b1fa804ef31e34267'>Set errno in vaswprintf in case vswprintf does not</a></td><td>June McEnroe</td><td><span title='2018-08-20 17:28:42 -0400'>2018-08-20</span></td></tr>
<tr><td class='commitgraph'>* </td><td><a href='/catgirl/commit/pls.c?h=1.7&amp;id=eac0f83efa3d6b1db2715c21d60b170a546ebc0a'>Factor out line editing to edit.c</a></td><td>June McEnroe</td><td><span title='2018-08-08 16:59:26 -0400'>2018-08-08</span></td></tr>
<tr><td class='commitgraph'>* </td><td><a href='/catgirl/commit/pl